Air drill stem



G. L. ADAMS AIR DRILL STEM Jan. 10, 1961 3 Sheets-Sheet 1 Filed May 8,1957 R. m WM mA L E G G H15 A rrozmsv G. L. ADAMS AIR DRILL STEM Jan.10, 1961 3 Sheets-Sheet 2 Filed May 8, 1957 INVENTOR. GEO/e6 6 LAoAMs /3y H15 A TTOENEY AIR DRILL STEM George L. Adams, Salem, Ohio, assignor toThe Salem Tool Company, Salem, Ohio, a corporation of Ohio Filed May 8,1957, Ser. No. 657,860

6 Claims. or. 285-330) This invention relates generally to earth boringof shot holes and the like and more particularly to the use of air underpressure while drilling to clean out the shot hole, together with animproved drill stem with a nonround drill stem joint for thetransmission of air to the bit to clean out the hole.

Boring shot holes in strip mine overburden with a bit and augerstructure presents many problems when it is necessary to drill throughcertain heavy shale and rock. The small pick-point bits used for augerdrilling take a long time to cut or chip through the rock and theyfrequently break off. A bit having rotary gear type teeth will cut therock much faster but requires air for cleaning hole and cooling of bitto prevent bit binding. Again threaded joints in the drill stringrequ.re special tools to make up the same and they are readily injured.-

Cuttings are removed from auger drilled holes by the continuousapplication of compressed air. This presented another problem. The augersections driving the bit remove the cuttings and allow the compressedair to escape without functioning for this purpose. Again the augersections did not provide sufficient weight on the bit.

These problems were solved by dispensing with the auger sections andreplacing them with a large cylindrical stem section that has moreweight than the auger and has only a small amount of clearance in thehole than that permitted by the auger. This restriction for the fulllength of the stem to the bit increased the velocity of the dischargeair and permitted the cutting to be continuously discharged.

The restriction created by the clearance between the hole and thecylindrical stem also reduced the required capacity of the aircompressor to flow the cuttings from the hole. This permitted the use ofa smaller and less expensive motor and compressor.

Another object of this invention is the provision of improved nonroundjoints between the stem sections that permit a quick means for couplingand uncoupling the stem sections, and a seal for the air passing throughthese joints. This seal provides an O-ring on cylindrical concentricprojections that are protected by a large shoulder on the nonround jointmembers when not in use and when inserted in a socket for use. Thenonround pin and socket members making up this improved joint may berotated in either direction and transmit power without becomingdisjointed.

Other objects and advantages appear hereinafter in the followingdescription and claims.

The accompanying drawings show for the purpose of exemplificationwithout limiting the claims thereto a practical embodiment illustratingthe principles of this invention wherein:

Fig. l is a view in vertical section of a vertical drilling rig.

Fig. 2 is a view similar to Fig. 1 with the drilling rig at a differentposition.

Fig. 3 is an enlarged sectional view of the joint between stem sections.

States Patent Fig. 4 is an enlarged perspective view of a seal on thesupports the carriage 3 on which is mounted the reduc-' tion gear box 4.The drive shaft 5 extends from the top of the carriage and is connectedby the coupling 6 to the bottom of the square Kelly bar 7. The Kelly bar7 is slidably mounted in the rotary mating socket driven by a driveshaft that extends upwardly from the engine 8 mounted on the truck bed.The second engine 10 actuates a compressor for supplying air underpressure at 315 cubic feet per minute to the hose and pipe 11 that isconnected through the coupling 12 to the drill string 13, the bottom ofwhich carries a rotary bit to cut a hole seven and three-fourths inchesor eight and three'fourths inches when the outside diameter of the stemis seven and one-quarter inches. A head 14 is in the form of a metal canhaving a flexible rubber collar around the drill stem which is placedover the hole. A discharge hole 15 in one side of the can permits thecutting to be blown from the head.

As shown in Fig. 3 the drillstring 13 is made up of consecutive tubularsections of stems 16 each having a square socket 17 in one end and amating pin 18 on the other end. The socket may be formed from stockwhich is cylindrical as indicated at 20 and welded to the tube 16 asshown at 21. A cylindrical bore 22 is provided at the inner end of thesquare socket 17.

The male or mating pin member 18 is square in cross section and is notas long as the socket is deep to provide the clearance 23 between thebottom of the socket and the end of the square section 18., The end ofthe pin 18 has a cylindrical nose 24 that fits the bore 22 with asliding clearance. The nose 24 has an annular groove 25 to receive theO-ring 26 or similar type sealing member that is deformed in the bore 22and seals therewith. The diameter of the nose 24 is about half thedimension of a square side of the pin 18. The annular groove 25 onthecylindrical nose 24 is located about halfway along the length of thenose. Thus'the O-ring is protected when the pin is in the open. The endof the nose is beveled as indicated at 27 to ward off anything thatengages the same so that it will not injure the O-ring. The end of thesquare pin 18 is likewise beveled as shown at 27 for the same purpose.Thus when the pin 18 is hoisted for stabbing the socket 17 of the lastdrill stem in the string, these beveled edges cause the section toglance sideways and thus avoid injury to the O-ring and the cylindricaland flat faces of the nose and pin.

The end 28 of the cylindrical portion of the socket 17 has buttingengagement with the shoulder 30 of the base of the pin. This is thegauge that forms the clearance 23 at the outer end of the pin. Thisshoulder is visible and any dirt that may be lodged thereon can easilybe seen and brushed off before stabbing the joint.

The bore 31 of the pin provides the compressed air passage from onesection 16 to the other. Although the pin and socket sections 18 and 17are made up and welded in the opposite ends'of the shell or casing 16,the stem could be made from solid tubular stock having the bore 31. Thiswould eliminate the large chambers 32 between the end of each section.

Each pin 18 has a pair of spaced holes 33 and 34 which pass transverselythrough the pin and are spaced from the bore 31. The socket 17 also hasthe holes 35 and Patented Jan. 10, 1961 36 which are aligned with theholes 33 and 34 when the shoulders 28 and 30 abut, for receiving thehair pin lock 37. In the structure of Figs. 1 to 4 the shells or casings16 of adjacent sections are spaced from each other which exposes thebend of the hair pin on one side and the ends on the other so one cantap the same with a hammer to insert or remove the hair pin.

In the structure of Figs. 5 and 6, the shells 16 of adjacent sectionsabut each other at the shoulders 28 and 30 and the corner is filleted at38. The socket 17 is provided with an arcuate slot 40 to permit the tineof a hammer to pry under the hair pin 37. This structure thus provides awider shoulder hearing at 28 and 30 and eliminates the external annularspace that clogs with dirt. The cylindrical bore 22 is formed in theexternally squared sleeve 41 that is slid into the socket 17 and iswelded as indicated at 42. The edge of the bore 22 is beveled as shownat 39. The inner end of the pin 18 is made in the shape of a spool 43,the flange 44 forming the shoulder 30 and the flange 45 providing theother end ofthe spool. Both spool flanges are welded as indicated at 46to the bore of the sleeve 47 which in turn is welded to the cylindricalcasing 16.

The swiveled seal coupling 12 shown in Fig. 7 comprises the flangesocket 50 having a flange member 51 with an annular rim 52 to enclosethe driving flange 53 welded to the nonround driving socket 54. Theflange 53 is bolted in place by the bolts 55 which pass through theretaining plate 56. Thus the flange has some wobbling play in thechamber formed by the rim 52. This may take care of small misalignmentsin the drill string when boring. The flange socket 50 is provided withbore 57 having the key ways 58 to receive the drive shaft.

The socket 54 has the nonround plug 60 welded therein to provide thecylindrical bore 61 to receive the mating nose 24 and its O-ring seal26. The bore 61 has at least three lateral holes 62 that also passthrough the walls of the socket 54 and connects with the annular chamber63 in the stationary block 64. A threaded passage 65 connects with thepipe 11 to supply compressed air to the bore 31 of the pin on the firstsection of the drill stem. The outer surface of the socket 54 iscylindrical and has a rotary fit in the bore 66 of the block 64. Twoannular sealing grooves 67 are provided in the bore 66 on opposite sidesof the chamber 63 and are provided with O-ring seals 68 which may be ofthe quadraform, to seal the compressed air from escaping as the socket54 rotates in the block 64.

I claim:

1. A stabbing joint between sections of an earth boring drill string thesections of which comprise an outer cylindrical tube, an exposedconcentric nonround pin on one end of said tubes, an exposed nonroundsocket on the other end of said tubes to receive said pin in drivingmating engagement, an annular radial abutment between the end of saidsocket and said pin to hold the end of said pin in spaced relation fromthe bottom of said socket, a cylindrical projection on the end of saidpin and smaller in diameter than said pin and concentric therewith, asmall complementary cylindrical socket coaxially and inwardly of saidnonround socket to receive said projection with clearance therebetween,an annular groove in the cylindrical portion of said projection, anannular elastomer ring in said groove and engaging said cylindricalsocket, said pin and projection and said socket having a passagetherethrough sealed by said elastomer, and a beveled end on saidcylindrical projection.

2. The stabbing joint of claim 1 characterized in that said sockets andpins have aligned transverse holes spaced from the passage therethrough,and locking key means in said holes to prevent disengagement betweensaid drill string sections.

3. The structure of claim 2 characterized in that said locking key meanshas a curved head and said socket is undercut under the curved head ofsaid locking key means.

4. A stabbing joint between sections of an earth boring drill stringhaving couplings of complementary nonround pin and socket members heldfrom parting by transverse locking means, characterized in that thedrill string and coupling have an axial passage therethrough, and eachcomplementary nonround pin and socket has consecutively engaging matingradial annular shoulders, mating nonround portions, second radialannular shoulders held from engagement by said first radial shoulders,and cylindrical portions with clearance therebetween, an annular groovein the cylindrical portion of the pin member spaced from said secondshoulder, an elastomer ring in said groove and engaging the cylindricalsocket to form a seal, and a.

References Cited in the file of this patent UNITED STATES PATENTS1,815,660 Walker July 21, 1931 1,873,304 DeMooy Aug. 23, 1932 2,008,096Clo July 16, 1935 2,013,962 Hutchens Sept. 10, 1935 2,676,820 Boice Apr.27, 1954 2,693,379 Rath Nov. 2, 1954

